}()
	}
	wg.Wait()
})

func TestIssue21181(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping with -short")
	}
	if *flagCheck {
		// slow, not worth repeating in -check
		t.Skip("skipping with -check set")
	}
	testenv.MustHaveGoBuild(t)

	warmupCache()

	for _, context := range contexts {

	"testing"
	"time"
)

func test18146(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping in short mode")
	}

	if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
		t.Skipf("skipping flaky test on %s; see golang.org/issue/18202", runtime.GOOS)
	}

	if runtime.GOARCH == "mips" || runtime.GOARCH == "mips64" {
		t.Skipf("skipping on %s", runtime.GOARCH)
	}

	attempts := 1000
	threads := 4

handling, at some cost in run time, is available by setting
GOEXPERIMENT=cgocheck2 at build time.

It is possible to defeat this enforcement by using the unsafe package,
and of course there is nothing stopping the C code from doing anything
it likes. However, programs that break these rules are likely to fail
in unexpected and unpredictable ways.

The runtime/cgo.Handle type can be used to safely pass Go values

// into Go.
func testCallbackCallers(t *testing.T) {
	if runtime.Compiler != "gc" {
		// The exact function names are not going to be the same.
		t.Skip("skipping for non-gc toolchain")
	}
	pc := make([]uintptr, 100)
	n := 0
	name := []string{
		"runtime.cgocallbackg1",
		"runtime.cgocallbackg",
		"runtime.cgocallback",
		"runtime.systemstack_switch",

		// implementation of a no-network check using 'unshare -n -r'.
		// Since this test does need root to work, we need to skip it.
		t.Skip("skipping root only test on a non-root builder")
	}
	if runtime.GOOS == "linux" {
		if _, err := os.Stat("/etc/alpine-release"); err == nil {
			t.Skip("skipping failing test on alpine - go.dev/issue/19938")
		}
	}

	// Launch some threads in C.
	const cts = 5
	C.trial(cts)

	"unicode/utf8"
)

// Scanner provides a convenient interface for reading data such as
// a file of newline-delimited lines of text. Successive calls to
// the [Scanner.Scan] method will step through the 'tokens' of a file, skipping
// the bytes between the tokens. The specification of a token is
// defined by a split function of type [SplitFunc]; the default split
// function breaks the input into lines with line termination stripped. [Scanner.Split]

	if runtime.Compiler != "gc" {
		// The exact function names are not going to be the same.
		t.Skip("skipping for non-gc toolchain")
	}
	if runtime.GOARCH != "amd64" {
		// TODO: support SEH on other architectures.
		t.Skip("skipping on non-amd64")
	}
	// Only frames in the test package are checked.
	want := []string{
		"test._Cfunc_backtrace",
		"test.testCallbackCallersSEH.func1.1",

func TestZip64(t *testing.T) {
	if testing.Short() {
		t.Skip("slow test; skipping")
	}
	t.Parallel()
	const size = 1 << 32 // before the "END\n" part
	buf := testZip64(t, size)
	testZip64DirectoryRecordLength(buf, t)
}

func TestZip64EdgeCase(t *testing.T) {
	if testing.Short() {
		t.Skip("slow test; skipping")
	}
	t.Parallel()
	// Test a zip file with uncompressed size 0xFFFFFFFF.

			macro := in.macros[name]
			if macro != nil {
				nesting++
				in.invokeMacro(macro)
				continue
			}
			fallthrough
		default:
			if tok == scanner.EOF && len(in.ifdefStack) > 0 {
				// We're skipping text but have run out of input with no #endif.
				in.Error("unclosed #ifdef or #ifndef")
			}
			in.beginningOfLine = tok == '\n'
			if in.enabled() {
				in.text = in.Stack.Text()
				return tok
			}

				break
			}
			i += o + 1
		}
		if s[i+1] == c1 && Equal(s[i:i+n], sep) {
			return i
		}
		i++
		fails++
		if fails >= 4+i>>4 && i < t {
			// Give up on IndexByte, it isn't skipping ahead
			// far enough to be better than Rabin-Karp.
			// Experiments (using IndexPeriodic) suggest
			// the cutover is about 16 byte skips.
			// TODO: if large prefixes of sep are matching